Electrical connector with improved contact retention

Abstract: A contact (10) has an intermediate body portion provided with respective side edges formed with a protruding convex portion (16) and a recessed concave portion (17), respectively. The contacts (10) are slidably inserted into respective channels (22) in the insulated housing (21) of an electrical connector (20), the channels (22) being separated by respective walls (23). When the contacts (10) are thus inserted into the channels (22), the convex portion (16) of one contact (10) cooperates with the concave portion (17) of an adjacent contact (10) to trap and deform the wall (23) therebetween, thereby exerting a resilient biasing force for retaining each contact (10) in its respective channel (22).

Description: The present invention relates to an electrical connector and, more particularly, to an electrical connector including a plurality of contacts having a superior retention system. Electrical connectors are used for connecting cables or other components in the electronic and aerospace industries. These electrical connectors include an insulated or dielectric housing having a plurality of respective channels receiving a corresponding plurality of contacts. These contacts are usually relatively thin, are elongated longitudinally, and have respective end portions providing terminals or equivalent elements. Each of the contacts has a body portion including side edges, and each of the side edges is provided with one or more laterally-projecting barbs. These barbs engage the respective sides of the channel in the insulated housing to effect an interference or press-fit therebetween, thereby retaining the contact within its respective channel. The contacts are inserted into their respective channels using high-speed automated equipment for producing a low-cost high-quality reliable product. The trend in electrical connectors is higher circuit density for product miniaturization without sacrificing product reliability. With higher circuit density, the contacts are necessarily smaller and are spaced closer together. As a result, the barbs on the contacts may not provide the desired retention force, especially where the electrical connector is intended for repeated "make and break" engagement over an extended period of time. Barbs are also ineffective in applications in which the walls of the housing are configured for high density applications, i.e. when the walls are relatively thin to conserve space. In these instances, the barbs can break through the plastic and make electrical contact with the adjacent contact terminal. This causes an electrical short which prevents the connector from operating properly. Accordingly, it is an object of the present invention to provide an electrical connector having an improved retention system for the plurality of contacts therein. The present invention consists in an electrical connector as defined in claim 1. An electrical connector according to the preamble of claim 1 is disclosed in US-A-3 923 356. There is disclosed herein an electrical connector including an insulated housing having a plurality of contacts positioned in thin walled cavities or channels, and at least first and second adjacent channels having respective portions separated therefrom by a thin wall; the wall has at least a portion thereof which may flex or be deformed. A plurality of contacts, including at least first and second contacts, are slidably inserted into the first and second channels, respectively. Each of the contacts is longitudinal and includes an intermediate body portion having first and second side edges, respectively. The first side edge includes a portion protruding laterally therefrom, and the second side edge includes a recessed portion. With this structure, the protruding portion of the first side edge of the second contact cooperates with the recessed portion of the second side edge of the first contact to trap the portion of the wall therebetween. As a result, the portion of the wall is deformed during the slidable insertion of the first and second contacts into the first and second channels, respectively, thereby providing a lateral biasing force on the respective contacts for improved retention of the contacts in the respective channels. In one embodiment, the protruding portion comprises a convex portion, and the recessed portion comprises a concave portion and nests with respects to the convex portion. Preferably, the first side edge of each contact is further provided with a pair of recesses, one on each side of the convex portion. In one case, each contact has a pair of spaced-apart arms integrally formed with the intermediate body portion of the contact and projecting longitudinally therefrom, and each contact further has a solder lead integrally formed with the intermediate body portion of the contact and projecting longitudinally therefrom oppositely of the pair of spaced-apart arms. The plurality of contacts may be arranged in a row of contacts, and the electrical connector may include multiple rows of contacts. An embodiment of the present invention will now be described by way of example with reference to the accompanying drawings in which: Fig.1 is a perspective view of an individual contact of the present invention. Fig. 2 is a perspective view of a typical electrical connector with which the teachings of the present invention may find particular utility, showing the multiple rows of contacts in the respective channels in the electrical connector. Fig. 3 is a partial cross-sectional view, taken across the lines 3-3 of Fig. 2, and showing some of the contacts arranged in a side-by-side relationship in their respective channels in the electrical connector. Fig. 4 corresponds substantially to Fig. 3, but shows the contacts in an exploded relationship with respect to the channels in the electrical connector. Fig. 5 is a cross-sectional view, taken across the lines 5-5 of Fig. 3, and drawn to an enlarged scale. Fig. 6 is a perspective view of one of the channels in the insulated housing of the electrical connector, showing the respective ramps for slidably guiding the respective contact therein. With reference to Fig. 1, the improved contact 10 of the present invention is generally an elongated relatively-thin member which is stamped out and formed from a suitable metal and, if desired, may be plated for electrical conductivity purposes. The contact 10 has an intermediate body portion 11, a pair of spaced-apart arms 12 at one end thereof and formed integrally therewith, and a solder lead 13 at the other and opposite end and, again, formed integrally therewith. It will be appreciated by those skilled in the art, however, that the particular contact 10 is only exemplary of a wide variety of contacts and equivalent members with which the present invention may find more particular utility. With this in mind, the intermediate body portion 11 of each contact 10 has first and second side edges 14 and 15, respectively. The first side edge 14 is provided with a protruding portion 16 (which is preferably convex) while the opposite second side edge 15 has a recessed portion 17 (which is preferably concave). The first side edge 14 is further provided with a pair of recesses 18 and 19, respectively, on each side of the protruding convex portion 16. With further reference again to Figs. 2-4, the contacts 10 are arranged in multiple rows in a electrical connector 10 including a dielectric or insulated housing 21 having multiple rows of respective channels 22. These channels 22 are separated by integrally-molded walls 23 within the housing 21, and each wall 23 has a reduced cross-section deformable portion 24. As shown more clearly in Fig. 4, the convex protruding portion 16 of the contact 10 is complementary to (and nests with) the concave recessed portion 17 of the adjacent contact 10 so as to trap the wall portion 24 therebetween and, more significantly, to flex or deform the wall portion 24 as shown more clearly in Fig. 5. As a result, a lateral biasing force is exerted on each contact 10, substantially transversely thereof, to provide an improved (and superior) retention of each contact 10 in its respective channel 22. It is worth noting, that the recesses 18, 19, provided on either side of the protruding convex portion 16, allow the plastic walls to relax and conform to the shape of the portion 16, thereby providing for a more effective retention of the contact 10 in the channels or cavities 22. As is best shown in Figure 3, each respective contact contributes to the lateral biasing force exerted on its adjacent contact. This provides an interlocking configuration between the contacts. With further reference to Figs. 5 and 6, each wall 23 has a reduced cross-section web portion 25 which has a top surface 26 and a bottom surface 27. The surfaces are provided to cooperate with surfaces of the contacts 10 to better retain the contacts in the channels. These surfaces 26 and 27 have inclined ramps 28 and 29, respectively, to facilitate the slidable insertion of each contact 10 into its respective channel 22 during the automated manufacturing process. With reference again to Fig. 2, the insulated housing 21 for the electrical connector 20 has a pair of bosses 30, each of which is provided with a pair of spring-loaded latching fingers 31 for mating engagement with a printed circuit board (not shown) or the like. These fingers provide the means to temporarily secure the connector to the board until the contacts 10 are permanently soldered to the board.

Claims: An electrical connector (20), comprising an insulated housing (21) having a plurality of channels (22) formed therein, including at least first and second adjacent channels having respective portions separated therefrom by a wall (23), and a plurality of contacts including at least first and second contacts (10) slidably inserted into the first and second channels (22), respectively, each of the first and second contacts (10) being longitudinal and including an intermediate body portion (11) having a side edge (14, 15) engaging the wall (23), characterised in that the wall (23) has at least a portion (24) thereof which is substantially deformable, and each of the intermediate body portions (11) has a first side edge (14) including a portion (16) protruding laterally therefrom and a second side edge (15) including a recessed portion (17), such that the protruding portion (16) of the first side edge (14) of the second contact cooperates with the recessed portion (17) of the second side edge (15) of the first contact to trap the portion (24) of the wall (23) therebetween, and such that the portion of the wall is deformed during the slidable insertion of the first and second contacts (10) into the first and second channels (22), respectively, thereby providing a lateral biasing force on the respective contacts (10) for improved retention of the contacts (10) in the respective channels (22). The electrical connector (20) of claim 1, wherein the protruding portion (16) comprises a convex portion (16), and wherein the recessed portion (17) comprises a concave portion (17) and nests with respect to the convex portion. The electrical connector (20) of claim 2, wherein the first side edge (14) of each contact (10) is further provided with a pair of recesses (18, 19), one on each side of the convex portion (16). The electrical connector (20) of claim 1, 2 or 3, wherein each contact (10) has a pair of spaced-apart arms (12) integrally formed with the intermediate body portion of the contact (10) and projecting longitudinally therefrom. The electrical connector (20) of claim 4, wherein each contact (10) further has a solder lead (13) integrally formed with the intermediate body portion (11) of the contact (10) and projecting longitudinally therefrom oppositely of the pair of spaced-apart arms (12). The electrical connector (20) of any one of the preceding claims, wherein the plurality of contacts (10) is arranged in a row of contacts. The electrical connector (20) of claim 6, further including multiple rows of contacts (10).

Inventors: BRENNIAN RONALD WOLFF JR, BUCHTER RANDOLPH LEE, KERNS IVAN PAUL, KOCHER TIMOTHY LEE, SCHULTZ EDMUND FRANKLYN JR, BRENNIAN, RONALD WOLFF, JR., BUCHTER, RANDOLPH LEE, KERNS, IVAN PAUL, KOCHER, TIMOTHY LEE, SCHULTZ, EDMUND FRANKLYN, JR.
Applicants: WHITAKER CORP, THE WHITAKER CORPORATION
Application year: 1994
Main classification: H01R13
IPC codes: H01R24, H01R13